Who Said I Wanted a Sister?
by Madi Winchester
Summary: When Sebastian stumbles across Joséphine, Clary, Jace and him find out that there's another Morgenstern out there. Is Joséphine on the side of the Shadowhunters... Or will she help Sebastian? *SPOILERS*
1. Chapter 1

**Who Said I Wanted a Sister?**

**A/N- this random idea for a fanfic just popped into my brain randomly one day and so I started writing :) enjoy!**

**Disclaimer: I do not own ANY of the TMI characters, only Joséphine :) **

**Warning: if you have not read City of Ashes and On, I suggest you do not read this fanfic, for there are spoilers :)**

Chapter 1

The girl sat afloat in a glass coffin, her fine hair flowing around her like a halo, her eyes closed. She had scars covering her body and faded Iratzes from battle. A woman, with dark red hair knelt beside the coffin.

"My daughter." She whispers, a tear slipping down her cheek. "What have I done to you? You're a monster." She cries and clutches the girls hand. She was dead. The monster that this woman had felt she created, though it wasn't her fault, was dead. Suddenly the girls eyes flew open, revealing her hazel eyes with flecks of gold and ice blue. She stares at the woman, who has bright emerald eyes and her hair falling in her face, tears flowing freely. The girl reaches out and grabs at her neck, holding tight, the woman chokes.

"H-h-help." She croaks out through the girls grasp and she finally lets go.

"Jocelyn." The fair haired girl snarls

"Joséphine." Jocelyn growls and lunges at Joséphine. Joséphine jumps out of the way quickly and gracefully, then goes around behind Jocelyn and knocks her head into the wall. Jocelyn stumbles back and swings at Joséphine but yet again Joséphine dodges it and sends a blow to Jocelyn's head, she falls to the ground but hits the glass coffin, shattering it. She stands up quickly and runs off, giving up, leaving Joséphine smirking in the cold damp room.

Two days later

"Hello, little sister." Sebastian walks up to Clary and smirks at her, causing her to clench the coffee cup in her hand.

"What are you doing here, Sebastian?"

"What? Can't a brother just say hi to their sister like it's a normal thing to do?"

"Fine. But just because I'm going along with you and Jace doesn't mean I'm gonna like, murder someone or do your dirty work for you."

"Dirty work would include murder, Clary."

"Whatever." She replies and crosses her arms.

"Clary." Sebastian says.

"What?" She asks.

"When I was gone.. Fighting. I found something. Something... Strange."

"Like what?"

"There was a girl. She had fine hair like mine and.. I don't know what color her eyes were because they were closed. And she was in a glass coffin, like mine." He tells her.

"Really? Let me see." She replies a little shaken. Who was this girl?

"Alright." Sebastian reaches his hand out for Clary to hold and she does hesitantly, then they walk to a tall building with wooden boards over windows and cracks in the walls. They walk through a doorway without the door and he leads her up four sets of stairs. When they arrive at the top, Clary sees a glass coffin and inside that glass coffin is a girl with fair hair floating around in the water. Her eyes are closed and it's obvious she has been up, there was blood mixed with the water and splattered on the walls. Her hair was matted and she had a bruise on her forehead. Sebastian touches the bruise and the girls eyes fly open. They're a beautiful hazel with flecks of gold and ice blue. The girl sits up in the water then stands up all together.

"Hello. I am Joséphine." She says in a voice like silk. She lifts herself out of the glass coffin and stands on front Clary and Sebastian, then says, "Well. Are you just gonna stand there or are you going to lead me to your home, allowing me to freshen up and change?"

"Oh. Of course. Follow us." Sebastian says and walks out of the building. The girl follows.

•••

Joséphine steps out of the spare bedroom, her fine hair flowing down her back. She had on a black spaghetti strap tank with a black leather jacket over top, black skinny jeans along with black combat boots. She smelled like Raspberries and she had on a red eyeshadow and lipstick.

"I'm done. I don't have to stay here.. Do I?" She asks Clary, who is sitting on a couch in the living room with a boy with golden hair and eyes to match.

"Well do you have anywhere to go?" He asks her. "I'm Jace by the way."

"No. But I'm sure I'll figure it out." She replies in a cool, even tone. "My name is Joséphine by the way. Joséphine.. Deschanel."

"Is that your REAL last name?" Clary asks. "Because it sounds to me like you had to think about what it was."

"No. But I don't plan on telling you."

"Well too bad, because you're going to be staying with us." She says. Joséphine walks forward to Clary and their faces are so close she can see her own reflection in Clary's scared eyes.

"My name. Is Joséphine Morgenstern. And I, Clary. Am your sister, and Jonathan's, obviously. So I'm going to be staying here, but you will not be telling me where, or where I cannot go. Understand?"

"Yes." She says. "I understand."

"Well good. Now that that's cleared.. Who wants FroYo?" Jace just shakes his head and so does Clary, they did NOT feel like celebrating. The only thought running through Clary's mind was: 'Who Said I Wanted a Sister?'


	2. Chapter 2

**A/N- sorry that I haven't posted in a while, I have had no idea what to write for this story. Serious writers block! Anyway, I THINK I have had a good idea for this story, so.. Hope you enjoy chapter 2! :)**

**Disclaimer: I do not own TMI (sadly) just the plot and Joséphine**

Chapter 2

"I can't believe I have a sister. She also seems a bit evil if I do say so myself." Clary tells Jace as she paces around his room. Jace sits on the bed, still under Sebastian's control. That made her sick. How could Sebastian do this to Jace? It doesn't really surprise her, but still.

"Clary, calm down. Maybe Joséphine could help all of us in what Sebastian needs."

"It's not what Sebastian needs. It's what he WANTS, Jace. Open. Your eyes. He wants to kill all Nephilim." She replies. He just shakes his head.

"When will you understand? I want this too, I need this. We all need this."

"Yeah. Then what happens if he kills all Nephilim? YOU'RE Nephilim, Jace."

"I don't count. I'm on Sebastian's side."

"Sebastian can't tell the difference between saving the world and destroying it. Where do you think he got that from?"

"Valentine." Jace replies.

"Yes. And you HATED Valentine."

"Yes, but now my eyes have been opened to what we really truly need. And what we need is the destruction of all Nephilim." He tells clary.

"No, it's NOT what we need!" She shouts, "it's not what ANY of us need and it never will be! Alec and Izzy aren't on Sebastian's side. He'll kill them, too. Just like he killed max. Do you really want that, Jace?" His eyes are blank and Clary groans. She just wanted Jace–the REAL Jace–back. She stops her pacing and sits down on the bed beside Jace. "Will you please.. Please just leave Sebastian's side? For me?" She asks, grabbing his hands. He sighs. He leans closer to her so that their foreheads are touching. He kisses her softly on the lips, then pulls apart, their foreheads still touching and his hand resting on the back of her head. He whispers against her mouth, "I can't. We all need this."

"But I don't want it." She whispers.

"What do I have to do to make you happy?" He asks her.

"This." She says, and before she realizes what she's doing, she's bringing a blade down across the mark that's binding Jace and Sebastian. He swears under his breath then falls limp on the bed. Panicking, clary shakes Jace's limp body and cries.

•••

Jace jolts up a couple of hours later, feeling different than before. He felt... Free. But of what, he had no idea.

Somebody stirs next to him causing him to look over and he sees Clary. His beloved Clary. Oh, by the angel he loved her.

"Jace? You're staring at me." She says in a small voice. Oh that voice. He felt like he hadn't heard it in forever.

"Sorry." He says. "I just.. It feels like I haven't seen you in forever."

"But you just saw me a couple of hours ago..." She trails off then gasps. She unbuttons his shirt quickly, causing him to gasp. What was she gonna do? Then she just goes still. Then he looks down and sees it. A red bloody mark, ripped open. A destroyed rune.

"What is that?" Jace asks Clary, a look of confusion in his eyes.

"It's a.. You were.. You were bound to Sebastian with that Rune. You would do what he said, Act like you two were brothers, you were... Comfortable around him and were on his side."

"I only came to help get you back." She tells Jace with a shaky, shock filled voice.

"Oh." Is all he replies with as he curls a lock of her hair around his fingers. He stares into her beautiful emerald green eyes, getting lost in them. He leans in closer, their foreheads are touching now and soon their lips come together. Jace reaches his arms around her, one hand is on the back of her head while the other arm is wrapped lightly around her waist. She loops her arms around his neck and kisses him back, causing him to push her down on the bed and start trailing kisses up her neck, then along her jaw, then finally he places a flurry of kisses on her lips. He seals the gap and they kiss until Jace catches his breath, pulling away.

"Are you the real Jace? MY Jace?" Clary asks him aloud.

"Yes. Sebastian can't control me." He replies.

"Sebastian can't what?" They hear a voice from the door. There stands Joséphine and Sebastian, their arms crossed. Jace and clary sit up, and Sebastian sees what's happened to the mark. He walks over quick and places an Iratze over the mark and clary watches as it slowly reforms. A sob escapes her as Sebastian takes him out of the room leaving clary and Joséphine alone.

"Why hello, little Sister." She says to Clary.

"Don't call me little sister. Sebastian already calls me that and I really don't like it." Says Clary, "it makes me feel small." She adds the last part in a small voice and looks over to see Joséphine smiling. It made Clary feel insecure because Joséphine seemed like the kind well... That was just like Sebastian.. In a way.

"Okay, Little Sis, wanna go do something fun? It's pretty boring in this place." Joséphine says as she sits down on the bed. Hesitant, Clary says, "Sure." Then Joséphine is grabbing her by the hand and leading them outside and to a shiny black jeep commander. 'Where did come from?' Clary thinks to herself. Joséphine hops into the drivers seat, telling clary to go to the passengers seat, which she does. When she hops in, Joséphine presses hard on the gas pedal and they're off to God knows where.


End file.
